A propeller consumes a certain power at stand of the vehicle, when the vehicle is not moving and it consumes another power for the creation of thrust, when the vehicle moves forward, whereby the propeller moves forward relatively to the air of the atmosphere or to the water wherein or on the vehicle moves.
The power consumed by the propeller varifies with the speed of the vehicle for any amount of desired thrust.
It was custom heretofore to use variable pitch propellers to obtain the best propeller efficiency at different speeds of the vehicle.
It was also proposed in the past to use propeller pairs of different numbers of propeller blades to drive ships by multiple propeller pairs. At those drives of ships it was also already proposed to use different pitches of the propellers to obtain a running of the ship with a minimum of vibration.
However, it was never tried to use a plurality of propeller-pairs with equal pitches of the propellers of the same pair but different pitches of the propellers of another pair and to varify automatically the power supply to the different propeller pairs in order to supply to each propeller pair the different powers for different speeds.
If however, such power division would become possible, the vehicle could be driven by propeller pairs of simple propellers with fixed-pitch, inexpensive propellers, but different pitches in different propeller pairs. And, such vehicle would then be able to run with good efficiencies at different forward speeds.